Laparoscopic surgery is commonly performed using access ports or trocars, which provide instrument access across an abdominal wall and into a gas pressurized abdominal cavity. Trocar seals within the trocars allow instrument changes with no or minimal loss in gas pressure. Such seals should be very durable even when challenged by the insertion of sharp-pointed instruments. They should be capable of accommodating a wide range of inserted instrumentation without leaking. They should be nearly friction-free so that they do not interfere with the action of the instrument. And they should not damage the inserted instruments. In addition, they should be cost-effective and user-friendly, and not add to the complexity of a surgical procedure. Also, due to the inherent limited confines of laparoscopic surgery, a continuing effort to reduce facial defects and to reduce interference between trocars, smaller or compact trocars are desirable while still providing the above-noted functionalities or enhanced functionalities.
Laparoscopic surgery is an evolving modality. Significant changes in instrumentation continue to challenge the trocar seals presently in use. Accordingly, there remains a continuing need to extend the range, durability and sensitivity of trocar seals.